Electronically commutated motors have been used to drive various types of apparatus, such as fans, by directly or indirectly coupling a shaft extending from the rotor assembly of the motor to the drive shaft of the fan. Although such motors are typically combined with the fan to provide a single assembly, such motors have not been integrated to the extent that the rotatable and stationary assemblies are separate, integral units of synthetic material formed around ferromagnetic components. Therefore, such motors are costly to manufacture and assemble.
Furthermore, the control circuitry required to electronically commutate a brushless AC motor is typically mounted remote from the motor or in proximity to the exterior of the rotatable assembly to permit cooling of the control circuitry. Such mounting results in an added cost to the motor and can cause an increase in the assembly time thereby resulting in additional cost.